Well perforating device



' T. L.A LONG WELL PERFORATING DEVICE Nov. ll, 1958 5 Sheets-Sheet l Filed June 7, 1954 Nov. H, 1958 T. L. LONG WELL PERFORATING DEVICE 3 Sheets-Sheet 2 Filed June '7, 19:54

. INVENTOR. THe/145 ONG imam/fr.;

Nov. 11, 195s- T. L. LONG 2,859,697

WELL PERFORATING DEVICE Filed June 7, 1954 5 Sheets-Sheetl 5 /lfroPA/frf.

atent WELL PERFRATING DEVICE rllhomas i.. Long, Houston, Tex., assigner, by mesne assignments, to .lohnston Testers, luc., Houston, r1`ex., a corporation of Texas Application .lune 7, 1954, Serial No. 434,856

3 Claims. (Cl. IGZ-21.8)

This invention relates to a well perforating device and more particularly to a well perforating device which is expendable and may be dropped free through a well tubing.

lt is the principal object of this invention to provide an expendable well perforating device employing shaped charges and a firing mechanism therefor, wherein said tiring mechanism is automatically actuated when the device issues from the lower end of a well tubing through which the device is dropped.

Another object of this invention is to provide an expendable well perforating device, employing a springloaded firing pin, and a latch for retaining said firing pin in its inoperative or cocked position in cooperation with the wall of a well tubing through which the device iS dropped, and wherein said latch means is automatically released to permit actuation of said tiring pin when said latch mechanism issues from the lower end of said tubing.

A further object of this invention is to provide an expendable well perforating device employing a firing pin adapted to be actuated by hydrostatic pressure existing within the well, and a latch for retaining said tiring pin in its inoperative or cocked position in cooperation with the wall of a well tubing through which the device is dropped, and wherein said latch means is automatically released to permit actuation of said firing pin when said latch mechanism issues from the lower end of said tubing.

A preferred form of my invention is illustrated and described, by wayof example, in the following specification and the accompanying drawings, wherein;

Fig. l is an elevational view of a perforating device embodying the principles of my invention.

Fig. 2 is a sectional view of the tiring mechanism of the tool shown in Fig. 1, showing the ring pin cocked and latched, the section being taken on line 2 2 of Fig. 4.

Fig. 3 is a similar view to that shown in Fig. 2 and illustrating the position of the elements immediately after firing.

Fig. 4 is a sectional view taken on line 4-4 of Fig. 2.

Fig. 5 is a sectional view taken on line 5-5 of Fig. 2.

Fig. 6 is a perspective view of one of the latch assemblies used to retain the firing pin in its cocked position.

Figs. 7 and 8 illustrate the manner in which the latch assemblies traverse a coupling joint in the well string.

Fig. 9 illustrates a modication of the tool illustrated in Figs. l to 8, inclusive.

Fig. 10 illustrates a modified form of the latch assembly.

In Fig. 1 the Well bore 10 has been drilled by the usual method of drilling, and a casing 11 has been inserted therein and cemented, as indicated at 12. After the casing 11 has been set, a production tubing 13 of relatively small diameter is inserted in the well so that its lower end is adjacent the upper level of the oil bearing formation.

The perforating device, generally indicated at 14, comprises a plurality of shaped charges 15, each pivotally mounted in a tubular skirt 16 adjacent an elongated opening 17 in the side of said skirt. The charges 15 are adapted to pivot from a position wherein their longitudinal axes are coincident with the axis of the tubular skirt 16 to permit passage thereof through the tubing 13 to a position wherein their longitudinal axes are at right angles to the axis of the skirt 16, after they emerge from the lower end of the tubing 13. It should be understood that the pivotal connections and the distribution of weight are arranged in such manner that the charges 15 will automatically assume the latter position when no longer conned by the well tubing 13.

Referring now to Fig. 2, the ring mechanism comprises a body 1S fastened to the upper end of the tubular skirt 16. A tubular plug 19 is adapted to be threaded into the lower end of the body 18 within the skirt 16 and sealed with respect to the body 18 by an O-ring seal 19a. A llame actuated blasting cap 21 is held in the body 18 by the plug 19. The plug 19 has an internal 'recess formed therein and a booster explosive charge 20 is contained in said recess. A length of primer cord 22 is con. nected to the lower end of the tubular plug 19, below the booster charge Ztl, and is connected to the rear surface of each of the shaped charges 15. Above the flame-actuated blasting cap 21, the body 18 is counterbored, as shown at 23, to receive a cylindrical plug 24 having two openings 25 formed therein designed to receive two impact operated blank cartridges 26. A sleeve 27 is adapted to be inserted in the counterbore 23 behind the sleeve 21 and cartridges 26 to retain the same in position within the body 18.

A tubular member 28 is threaded into the upper end of body 18 and bears against an O-ring seal '29, which seals the connection between the body 18 and the tubular member 2S. A firing pin Sil is slidably mounted in the tubular member 23 with its upper end extending upwardly beyond the upper end of the member 28. The lower end of the tubular member 28 is counterbored as s'hown at 31. A spring 32 is received within said counterbore and bears against the upper end thereof, and is confined at its lower end by a ring nut 33 threaded on the lower end of the firing pin 3i). The spring 32 normally urges the ring pin toward its lowermost position, illustrated in Fig. 3, wherein the tiring nut 33 will strike and lire the cartridges 26.

The upper end of the tubular member 28 has a plurality of slots 34' extending inwardly from the outer surface thereof to adjacent, but not intersecting, the central tubular passage therethrough. Three latch members 35 are mounted with their lower ends in the slots 34, and their upper ends abutting a downwardly facing shoulder 36 formed on the outer surface of the tiring pin 3i) ad t jacent the upper end thereof. The lower surface of the shoulder 36 on the tiring pin 30 is tapered downwardly and inwardly, as illustrated in Fig. 2 of the drawings. The upper ends 37 of the latch members 35 are similarly tapered downwardly and inwardly, whereby the firing pin, being urged downwardly by the spring 32, tends to force the upper ends of the latch members outwardly to release the firing pin.

An annular groove 38 `is formed in the outer surface of the tubular member 28 and intersects the mid-portion of the slots 34 formed therein. Each of the latch members 35 is formed with a laterally extending notch 39 formed in its lower end. As best seen in Fig. 5, when said latch' members 35 are inserted in the slots 34, a circular spring 4t?, received in the annular groove 38 and the notches 39, holds the lower ends of the latch members 35 in their` Patented Nov. 1l, 1958 and 48. The upper end of the bar 41 is charnfered as indicated at 49, the chamfer being on the corner of the bar which will be adjacent the firing pin 30 and Awhich also,is,:adjacentythdlatchn'member135.; The bar 42 is similarly vchu'nfered-as shown at 750.

lnzthe'use of the perforatingitool shown in frFigs.. .l

to, 8, inclusive,- the; parts .are assembled asv illustratedl- 4in Figs...l and-2 and the` device is inserted inthe .upper end each'. ofthe charges 15-emer=ges from the lower end of Y they tubing 13, yitvvill automatically swing outwardlyinto its .horizontalpositionin the Ymanner illustratedinFigs.'v

l and ,2, and whenatheilatchassernbly issuesk from thea,

bottom of said tubing 13, the bevelffaces36=and 37 cog` operateV .to force'. .the latch members 35' butwardly; since therolglersAthrough 48. are nolonger in contactwith the .innerpwall of :the tubing 13. j, When the latchrmembers move outwardly, `and 'no longer contact the shoulder-- 36,'thef springf32 forces the-ringpindownwardl and the=firing nut 33.strikes the cartridges 26. The flame fromthe cartridgesz ignites the blasting cap 21, which in turn. sets off 'the booster charge 20, firing the primercord` 22, andcausingeach of the shapecharges to lire and penetrate the casing 11, the cementY 12 and the oil bearing formation.

able anddrop down into the bottom of the Well bore.

Referring now to the modication shown in Fig. 9,

the main parts are generally the same as those shown inFigs'. 1 through 8 and are given the same reference numerals as used therein. One difference between the two structures is thatithe,counterbore31Y and the spring 32are omitted, and in place'thereof an O-ring seal 50a is inserted in a groove lformed on the inner-surface of theftubular `member 28y and seals against the tiring pin l 31.' Another difference is that the latch members 52 have a projecting lug53' at their lower end, which is adapted to be received within a plurality of bores 54 providedv in the upperA end of the tubular member 28 adjacent the centralrbore thereof.l A spring 55.is inserted in the bore 54 below .the eXtendinglugSS of the latch member 52.

Any. partsof the perforating mechanism remaining after the firing thereof are expend-` f againstthe innerasurfaje of.a welltubking throughwhichg an elongated bar 57, having three rollers 58, 59 and 60 rotatably mounted thereon, is pivotally fastened adjacent its mideportion with la pin 61 to the upper portion of the latch .member-52 above the offset 56.- The pin 61 Aextends through the central roller 59 and is threaded into thelatch member 52. By using an offset latch memberv 52, only one bar carrying three rollers 58,59 and 60 is member 28.

Y required, since thevroller's are mounted on the centerline of the projection S3 which is in contact with the tubular,

The operation ofthe modification kshown in Figs.y 8

and 9 is the same in all respects with that shown in Figs. l

throughy 8, the differences, being thatthe ringpin in` stead of being forced downwardly by an actuating spring, is forced downwardly 'by they hydrostatic pressure Iacting against theV upper end thereof. The lower end of the rod 30 is subjected to atmQSPheric pressure in theopenarea Within the sleeve 27, since thewell fluid pressure is prevented from entering into saidopenarea by means of whichl will automatically tire toperforate the casing andwell when the device issues from the lower end of said production tubing.

ILS .further ,eidelltiithahl have provided a spring` of s aidflateh, barsfrat least -three rollersrtpi votallysecuredu actuatedvrerforatns..deyiee, .which may, be `used in wells. with or without `fluid in the well at the time of use. I have further provided a hydrostatically actuated perforating device v'which is safe and easy to handle for use with' wells having fluid therein, said hydrostatcally operated, device reducing the hazardofanlaccidental firing before insertion into the upper end' of the production tubing, and being capablefof firing only Whenguid is present in the well to supply the actuating force to the firing pin.

While I have shown and described the preferredjforrn's of `myinvention, it is evident' that certain changes maybe i made therein by those skilled in the art without departing from thetspirit-= of thefinventionas-defined` in Ythefrappended claims. 'Y Having thus described my invention, "what desire to secure by Letters Patent is:

l. A firing mechanism for a well perforating device comprising a housingga cartridge mounted inisaid hous ing, a firingfpinslidablyfmounted invsaidhousingeaboveI said cartridge and extending :upwardly abe-ve said housing; said firing pin 'being adapted to strike said cartridge,t meansfoncausingsaiddring pin tostrike saidrcartridge, latch means.. forretaining Ysaid firing pin inoperative com prising a downwardly facing ,abutment t formed. on :sai firing vpin edieCentthenuppeffend thereea pluralityV of latch bars axially g confined with L .their opposite ends ins abutting relation with said downwardlyfacingabutment andthe; unrest-end of ...saldi-housingrespeetively, .a VP111- Y, lrality of. barsfpivotally connected-fatftheir` mid-pointsv to; Said -1ateh barst adieentfthe midrertion thereof,` and a plurality Ofkrollers l.rotatably lnountedv en Y each ofsaim la-st-mentionedf bars, ,saidy rollers being g E adapted to ,bean

=I claim 'andt the gdevicejs to -beidroppedy toy-retain 4jsaid.- latchbars-in i 'Y latching position. v-

2- ,A kings-mechanism tierna Well; @efferati-ng. device:A f' l' adapted tofbe lowered-through@ wellgtubing,.comprising;g 11 a housing, ,initial .firing meansmounted-in said housing,,a rins rims'lidablv mounted-fin @Seid housing abete Sat. initial rin g .means, trneans .for ,biasing said I firing pin t strike said initial firing means, latch means. forjretaining saidffringpin inoperative comprising a plurality yo'f.latchA bars, means for .restraining Voutwardmovement Yof the lower; ends;.ofl,said.latch bars, Vabutment meansicn the upper end of. each of said'latchbarS, downwardly facing abutment'means, en an. upper;portionyptV said firingj-pin, f at least one of said,abutmentmeansI being tapereddown--. wardlyand inwardly,.land meansy carried by veach of said latch bars for contacting...thewell tubingand for .urging said abutmentMmeans-intof mutual engagement when the ring mechanismis withinfthe` well tubing comprising'at least one IollerbarA-andrthree walljengaging,-grollers,jv pivo means securing each said roller bar to its respective latc bar, 4Imeans seeuring-ets1east twoupf t Seid.V wall:` engaging rollers to its gespective". roller bar above and belowgsaiy pivot means and means securing one of said wall engagv ing rollers to` its., n respective, roller` bar ,the t vicinity 'of said pivotmeans. l p 1 3. yA, firingmech-.anisnl for.afwell perforating' device adapted to. be lowered throughQa welltubing comprising a housing: initial ,tiring .means vrr'iounted.V in said housing, firing pin' slidably mounted insaid.housingabove'saidY initial firing means,.means.,forgcausingtsaid,firing pinto Y strike said initial firing means, and .latch'rneansfplfor holdfl ing said. fr-inggpirli`- inoperatiye comprising A a plurality of latch bars having abutment means on their upper en dsjf downwardly -feensrabut-mentrmeans en said tiring pin; at least one '.of. saidv abutment: meansbengzfaped '-dOW wardly `and.finwarslm t-meansrforwrestrainins :fmtwerd movementv of them lowerv ends-ofsaid'latch bars, .a roller?` bar'pivotally secured at 1a central,-pointftherealong to each to each roller:bar,:theacentralroller:being pivoted. at said l central poing-.said rollers.beingarranged'to contact the W611i tllbDg= alici;w toeurger saiditlatchsbarsl inwardlyv to Aenj- References Cited in the le of this patent UNITED STATES PATENTS Spencer Apr. 21, 1936 Collins Sept. 15, 1942 6 Collins J'an. 5, 1943 Couch Aug. 24, 1943 Thompson et al. Mar. 6, 1951 Abendrot-h Dec. 29, 1953 Kanady Apr. 12, 1955 FOREIGN PATENTS France Mar. 11, 1953 

